I have upgraded my bike with a new front suspension fork. Bought and fitted an adaptor from Shimano as the fork is laid out for 160mm (Postmount 6) and my disc front wheel brake rotor is 180mm. However, when I fitted the wheel I noticed that the outside diameter of the rotor catches against the caliper.
The problem disappears if I fit a spacer between the fork and the adaptor but that is not a solution that I am keen on. The wheel can rotate but the problem is clearly noticeable.
The fork and the caliper are both post mount and I have double checked that the adaptor is fitted the right way up.
What am I missing?